Flat panel display technology has been involved in a worldwide effort to add color to flat panel display devices. One of the most successful attempts at this has been Active Matrix Liquid Crystal Displays (AMLCD). However, AMLCD has not been able to extend its technology to large displays because of yield problems in sizes 14 inch diagonal and larger.
Another flat panel technology, ac Plasma Display Panels (ACPDP) is readily extended to large sizes but has significant penalties when phosphors are added to its interior structure.
A number of literature references have described technology which attempts to duplicate some properties of the cathode ray tube (CRT) in a flat panel design. For example, U.S. Pat. No. 4,577,133 to Wilson describes the use of a patterned cold cathode which is electrically addressed. The same patent depends on the use of an internal electron multiplier to gain sufficient electron flow to meaningfully excite the phosphors. The use of a multichannel plate electron multiplier (MCP) complicates and makes the resulting structure expensive when applied on a large scale. Moreover, additional problems arise in manufacturing due to the multiple process steps necessary to form the individual cold cathode emitters. Accordingly, it is readily recognized that simple processes are desired when transferred to full scale manufacturing operations.
Field emission from microtips and thin diamond films has also been described in the literature as it applies to flat panel displays. Microtips require multiple step processes to fabricate and provide problems when applied to large areas. Moreover, simple diamond films do not have a current control feature as do the microtips and are subject to local high emission which can destroy the local film due to heating. Simple diamond films require patterning of the film and the underlying electrodes in order to isolate the individual cell site. Furthermore, the microtip and the diamond film require scanning which reduces light output intensity as the display size is increased.
The present invention is intended to address the problems of the prior art by including current control by requiring photon stimulated emission similar to a photo transistor. The fields for photo stimulated field emission are less than in a simple field emission case. In addition, the photo stimulated field emitter film does not require patterning since the light input provides the pattern.
Accordingly, an object of the present invention is to provide a large full color flat panel display with high resolution. Another object is to provide a photon coupled flat panel display so that the color structures normally found on the interior are actually exterior to a conventional monochrome flat panel display. A further object of the invention is to provide a non-patterned photo electron emitter which converts the light input pattern from any suitable monochromatic source to an electron pattern which is used to excite color phosphors. An additional object of the present invention is to provide a large full color flat panel display with high resolution that is economical to manufacture. Yet another object of the present invention is to utilize field assisted photo electron emission to provide the equivalent of a three terminal or transistor like action within the non-patterned electron emitter.